If you’ve lived in South Florida for a while you know hurricane forecasting has improved. It’s far from an exact science as the National Hurricane Center meteorologists are quick to point out but it is an improving science. In recent years, it’s not just that the cone of uncertainty has become smaller, it’s that for the most part, forecasting has become more accurate. It goes without saying that the longer-range the forecast, the greater the uncertainty. But what difference does a day make in forecasting? That'll be about 40 miles.
Naturally, the five-day forecast introduces the greatest uncertainty but even then, it’s pretty good these days. 67% of the time the system travels through the cone of uncertainty and the margin of error is 210 miles.
Now, what do those 210 miles represent? Five days out the average storm passes 210 miles from the center of the projected path. As you see Dorian’s cone essentially covering the entire state of Florida. It’s 350 miles from Miami to Jacksonville. Now, NHC’s accuracy improves about 40 miles per day. So, this is how it breaks down:
- Four days out: 170 miles of variance
- Three days out 130 miles of variance
- Two days out 90 miles of variance
- One day out 50 miles of variance
For perspective on the 50 miles, that’s about the distance from Miami to Boca. That’s pretty darn good about a day out. Be careful to see what’s real and not what you’d prefer to see happen with forecast projections.
Photo by: ERIKA SANTELICES/AFP/Getty Images